Civilian and military radio systems can be implemented on different platforms to perform diverse warfare, location, communication, navigation and identification functions. Platforms can include backpacks, satellites, rockets, vehicles, naval vessels, aircraft, shelters, or other structures. Radio systems can even be handheld systems. The communication functions can involve the reception and the transmission of voice, data, or both by computer equipment or by personnel.
Radio systems typically include electronic filters. Generally, electronic filters are signal processing devices used in radio frequency (RF) communications, electronic warfare, and all other communication, navigation, and identification (CNI) systems to improve the signal-to-noise ratio and to reject both external and internal interference. Conventionally, multi-band receiver and transmitter architectures require multiple bandpass filters with a variety of fixed frequencies and bandwidths. The multiple bandpass filters have frequencies and bandwidths configured for each individual CNI, EW, and radar signal type waveform or other waveform signal. For example, a separate bandpass filter is often required for each RF application. Utilizing multiple bandpass filters increases the size and costs associated with the receiver and transmitter. Reducing the number of bandpass filters, which are bulky and expensive, can dramatically reduce the overall size and cost of the radio system.
Therefore, there is a need and desire for a programmable filter that eliminates the need for multiple filters in multi-band radio systems and offers a solution for future open system architectures. There is also a need and desire for a programmable filter where the filter parameters can be varied to adjust filtering bandwidths and tuning. Further, there is also a need and desire for a programmable filter that reduces the size and costs associated with multiple bandpass filters.